It is known to provide an air bag module with an air bag and one or more tethers that help control the inflated configuration of the air bag. It is also known to provide a tether having an effective length that can be selectively adjusted to help control the inflated configuration of the air bag in response to sensed vehicle or occupant conditions. For example, a solenoid may be actuatable to release a tether in response to a sensed condition indicative of a position of a vehicle seat or a position of an occupant of the seat associated with the air bag module.